Dynamic Magnesium Replacement Strategies and 28-Day Mortality in Non-Cardiac Critically Ill Patients With Hypomagnesemia: A Target Trial Emulation

NCT07380542 | Completed

• 1 other identifier: HChen-MgReple2025
• Study Type: observational
• Target: 12,887
• Locations: 1 country
• Sites: 1

Brief Summary

This study looks at how different ways of giving magnesium (a nutrient) affect the risk of death within 28 days for adults with low magnesium levels who are in the intensive care unit (ICU) for non-heart-related reasons. We will use data from past ICU patients (2008-2019) to compare three approaches: No magnesium treatment (even if levels are low); Daily magnesium treatment (regardless of daily levels); Dynamic treatment (only giving magnesium when daily tests show low levels). The goal is to find out which strategy is safest and most effective for this group of patients.

Conditions

Hypomagnesemia

Keywords

Magnesium Replacement Therapy; 28-Day Mortality; Intensive Care Unit Patients; Target Trial Emulation; Retrospective Cohort Study

Outcome Measures

Primary Outcomes (1)

• 28-Day All-Cause Mortality

  Death from any cause within 28 days after t0 (t0 = the first time serum magnesium \<1.7 mg/dL is detected within 72 hours of hospital admission)

  28 days after t0

Study Arms (3)

Never Treat Group

Patients with hypomagnesemia who received no magnesium replacement therapy during their ICU stay, regardless of daily serum magnesium levels

Always Treat Group

Patients with hypomagnesemia who received daily magnesium replacement therapy during their ICU stay, regardless of daily serum magnesium levels

Dynamic Treat Group

Patients with hypomagnesemia who received magnesium replacement therapy only on days when their daily serum magnesium level was \<1.7 mg/dL during their ICU stay

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

This study includes adult (≥18 years) non-cardiac critically ill patients with hypomagnesemia (serum magnesium \< 1.7 mg/dL) within 72 hours of ICU admission, identified from the MIMIC-IV (version 3.1) database (2008-2019). Patients with cardiac-related admission or missing key data are excluded. The population represents a diverse cohort of non-cardiac ICU patients (e.g., respiratory, gastrointestinal, neurological etiologies) to evaluate the association between dynamic magnesium replacement strategies and 28-day mortality.

You may qualify if:

• Age ≥ 18 years.
• Admitted to the Intensive Care Unit (ICU).
• Developed hypomagnesemia (Serum Magnesium \< 1.7 mg/dL) within the first 72 hours of ICU admission.

You may not qualify if:

• Admitted due to cardiac or cardiosurgical causes (e.g., Cardiac Surgery Recovery Unit, CCU, CVICU).
• Underwent cardiac surgery during hospitalization (identified by ICD-9/10 procedure codes).
• Primary discharge diagnosis of major cardiac conditions (e.g., myocardial infarction, heart failure, arrhythmias).

Sponsors & Collaborators

• Fujian Provincial Hospital: lead

Study Sites (1)

Fujian Provincial Hospital

Fuzhou, Fujian, 350001, China

Location

Related Publications (2)

• Hernan MA, Robins JM. Using Big Data to Emulate a Target Trial When a Randomized Trial Is Not Available. Am J Epidemiol. 2016 Apr 15;183(8):758-64. doi: 10.1093/aje/kwv254. Epub 2016 Mar 18.

  PMID: 26994063 BACKGROUND

• Johnson AEW, Bulgarelli L, Shen L, Gayles A, Shammout A, Horng S, Pollard TJ, Hao S, Moody B, Gow B, Lehman LH, Celi LA, Mark RG. MIMIC-IV, a freely accessible electronic health record dataset. Sci Data. 2023 Jan 3;10(1):1. doi: 10.1038/s41597-022-01899-x.

  PMID: 36596836 BACKGROUND

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Study Record Dates

• First Submitted: January 24, 2026
• First Posted: February 2, 2026
• Study Start: September 1, 2025
• Primary Completion: December 31, 2025
• Study Completion: December 31, 2025
• Last Updated: February 2, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)